Emissions control device

Abstract

An emissions control device for treating or removing pollutants from an exhaust gas produced by an internal combustion engine is disclosed. The emissions control device comprises a solid foam layer disposed on a substrate, wherein the solid foam layer disposed on a substrate has an open cell structure and comprises a particulate material which is a catalytic material comprising a catalytically active metal supported on a support material.

1 . An emissions control device for treating or removing pollutants from an exhaust gas produced by an internal combustion engine, wherein the emissions control device comprises a solid foam layer disposed on a substrate, and wherein the solid foam layer disposed on a substrate has an open cell structure and comprises a particulate material which is a catalytic material comprising a catalytically active metal supported on a support material. 
     
     
         2 . The emissions control device according to  claim 1 , the solid foam layer has a cell volume, wherein more than 20% of the cell volume is interconnected. 
     
     
         3 . The emissions control device according to  claim 1 , wherein the solid foam layer has a median pore diameter of 1-100 µm. 
     
     
         4 . The emissions control device according to  claim 1 , wherein the solid foam layer comprises bubble like structures having a size distribution in the range of 5 µm-500 µm. 
     
     
         5 . The emissions control device according to  claim 1 , wherein the solid foam layer comprises a partially collapsed structure. 
     
     
         6 . The emissions control device according to  claim 1 , wherein the thickness of the solid foam layer is no more than 500 µm. 
     
     
         7 . The emissions control device according to  claim 1 , wherein the solid foam layer is substantially localized on the walls of the channels. 
     
     
         8 . The emissions control device according to  claim 1 , wherein the substrate is a porous monolith. 
     
     
         9 . The emissions control device according to  claim 1 , wherein the catalytically active metal is at least one transition metal selected from iron, copper, nickel, gold, platinum, palladium, rhodium, and ruthenium. 
     
     
         10 . The emissions control device according to  claim 1 , wherein the support material is a refractory oxide, a metal aluminate or a zeolite. 
     
     
         11 . The emissions control device according to  claim 1 , wherein the support material is a refractory oxide, which is selected from the group consisting of alumina, silica, titania, magnesia, zirconia, ceria, lanthana and a mixed or composite oxide of two or more thereof, such as silica-alumina, titania-alumina, zirconia-alumina, ceria-alumina, titania-silica, zirconia-silica, zirconia-titania, ceria zirconia, ceria-zirconia-alumina or alumina-magnesium oxide. 
     
     
         12 . The emissions control device according to  claim 1 , wherein the particulate material is a metal oxide based SCR catalyst formulation, a molecular sieve based SCR catalyst formulation or a mixture thereof. 
     
     
         13 . The emissions control device according to  claim 12 , wherein the particulate material is a molecular sieve based SCR catalyst formulation, preferably the molecular sieve based SCR catalyst formulation comprises a transition metal exchanged molecular sieve. 
     
     
         14 . The emissions control device according to  claim 13 , wherein the molecular sieve based SCR catalyst formulation comprises a transition metal exchanged molecular sieve. 
     
     
         15 . The emissions control device according to  claim 14 , wherein the transition metal of the transition metal exchanged molecular sieve is copper and the molecular sieve is a zeolite having a framework structure represented by a Framework Type Code CHA.